That’s kind of an unreasonable solution to this problem. I don’t think the 15% rate has changed any in the last multiple decades. I think many people tip 20% because the math is easier.

Tipping doesn’t need to be a source of anxiety. If the act of figuring out your tip is the sole reason you don’t go out for a nice meal on a special occasion, I think this is something to talk to a therapist or confidant about.